Schematic drawing showing the external hepatic branches of the portal vein in ruminants. 1: Portal vein; 2: Gastroduodenal vein; 3: Cranial pancreaticoduodenal vein; 4: Right gastric vein; 5: Right gastroepiploic vein; 6: Omental branches; 7: Splenic vein; 8: Epipolic branch; 9: Right ruminal vein; 10: Reticular vein; 11: Left ruminal vein; 12: Left gastric vein; 13: Accessory reticular vein; 14: Left gastroepiploic vein; 15: Cranial mesenteric vein; 16: Caudal duodenal (Caudal pancreaticoduodenal) vein; 17: Jejunal veins; 18: Ileal vein; 19: Ileocolic vein; 20: Caecal vein; 21: Caecal branches; 22: Mesenteric ileal vein; 23: Antimesenteric ileal vein; 24: A common trunk of colic branches and right colic veins; 25: Right colic veins; 26: Colic branches; 27: Caudal mesenteric vein; 28: Middle colic vein; 29: Left colic vein.